This is a competitive renewal of the CBSR that established the Wisconsin Center for Affective Science. Our Center is focused on the social and psychobiological contributions to affective style. Affective style refers to a brad range of individual difference in emotion-related processes. Such individual differences are hypothesized to play a key role in governing vulnerability to psychopathology. The distal and proximal influences on the development of internalizing disorders and behavioral inhibition are central features of our research, long with a focus on the underlying neural circuitry associated with these characteristics, with a particular emphasis on prefrontal cortex, the amygdala and the HPA axis. An important component of affective style is the time course of affective responding, particularly the recovery function following a negative event. This we have described as affective chronometry and a number of proposed studies will further develop this concept and explore its neural substrates and behavioral correlates. Common measures are included in very Center project to facilitate comparisons across studies. Our center will consist of four projects that are supported by three cores. In Project (Davidson) we will examine the neural circuitry underlying individual differences in affective chronometry in both normal individuals and patients with affective disorders using a variety of techniques including quantitative brain electric activity measures, positron emission tomography and functional magnetic resonance imaging. In Project (Kalin) we will characterize the detailed circuitry underlying fearful temperaments in rhesus monkeys using reversible inactivation techniques to examine the contribution of the amygdala to this behavior. The roles of glutamate and GABA in the amygdala will be explore with intra-amygdaloid infusions of agonists and antagonists. In Project (Goldsmith), we will examine a batter of central and autonomic psychophysiological measures related to affective style in monozygotic (MZ) and dizygotic (DZ) twin children. A second component of this project will involve more intensive study of a sample of MZ and DZ twins selected to be at-risk for internalizing disorders. Project (Essex) will continue to be carried out in conjunction with the Wisconsin family and Work Project, a study that began in 1989 with 570 families This project will examine early individual measures of temperament during the preschool years. Relations between these early social factors and individual child characteristics and biological measures will also be examined. These projects will be supported by an Administrative Core, a Behavioral Assessment Core and a Biological Measures Core. This Center will continue to significantly advance our understanding of the social, psychological and biological bases of individual differences in affective style and will yield important new information that will facilitate our understanding of emotion disorders.